1. Field of the Invention
The present invention relates to a vending machine which picks up a vibration of a receiving plate to detect whether or not goods have been carried out.
2. Description of the Related Art
Conventionally, as a vending machine of this type, there has been known one described in Japanese Patent Application Laid-Open No. 6-348935.
In this vending machine, when a customer inserts a coin and presses a goods selection switch, a goods carrying-out device of a column corresponding to selected goods is driven and the selected goods fall on a receiving plate of a goods taking-out port. When the goods fall, the goods collide with the receiving plate and a vibration is generated in the receiving plate. A vibration sensor detects the vibration of the receiving plate, and a judging device judges that the goods have been carried out according to a vibration detection signal. On the other hand, when the vibration sensor does not detect a vibration of the receiving plate, the judging device judges that goods have not been carried out to the goods taking-out port and returns the inserted coin to the customer. Consequently, an inconvenience that the inserted coin is taken into the vending machine without being exchanged with goods is prevented from occurring.
In addition, among other types of vending machines, there is one which stops driving of a goods carrying-out device and shifts to a sales standby state of a next goods to be sold when a vibration sensor detects a falling vibration.
Incidentally, the vibration sensor is installed in a part where a vibration can be detected accurately, that is, a part of the receiving plate which is subjected to a largest vibration impact. Consequently, it is likely that a sensing section of the vibration sensor is broken or a joint section of a lead wire is broken. In addition, it is also likely that water drops adhere to adjacent lead wires due to dew concentration in the vending machine to cause short circuit.
There is no problem if such a deficiency is found immediately when it occurs and a measure is taken to cope with a failure of the vibration sensor. However, actually, it is likely that long time elapses until the failure is recognized, that is, until the judging device judges that a vibration which is naturally generated has not been generated. Due to this problem, in the former vending machine, it is likely that a situation in which an inserted coin is taken into the vending machine by mistake frequently occurs. In addition, in the latter vending machine, it is likely that the goods carrying-out device continues to be driven even after goods have already been carried out, and following goods are also carried out by mistake.
In view of the above-described conventional problems, it is an object of the present invention to provide a vending machine which can find a failure of a vibration detecting device promptly and accurately.
A vending machine in accordance with a first aspect of the present invention includes: a goods carrying-out device which is driven so as to carry out goods when a goods selection signal of a goods selection switch is inputted; a receiving plate which receives the goods carried out from the goods carrying-out device; a vibration detecting device which is capable of detecting a vibration generated in the receiving plate; a vibrating device which strikes the receiving plate to cause the receiving plate to generate a vibration in the receiving plate; and a judging device which judges whether the vibration detecting device is normal or abnormal according to whether or not the vibration detecting device has detected the vibration generated by the strike of the vibrating device.
According to the first aspect of the present invention, the receiving plate is vibrated by driving the vibrating device. Here, it is judged that the vibration detecting device is normal when it detects the vibration. On the other hand, it is judged that the vibration detecting device is abnormal when it does not detect the vibration.
The above-described object and other objects of the present invention, and characteristics and advantages thereof will be apparent from the following description and accompanying drawings.